The present invention relates generally to lighting devices such as light emitting diode (LED) drivers. More particularly, an embodiment of an invention as disclosed herein relates to an electrically isolated method for digitally dimming, configuring and updating the firmware of a programmable lighting device through wireless communication and volatile memory.
For many luminaire manufacturers it may be desirable to configure the operating parameters of LED drivers before shipping to customers for installation, without requiring coupling of the LED drivers to a mains power source. It is further desirable to configure various operating parameters of the LED driver at other stages of application, again without having to apply mains input power to the LED driver. For example, when a driver is first removed from its packaging, it may be desired to apply a default configuration to satisfy the needs for most of the LED drivers at a particular installation. Further, once a new driver is installed with other LED drivers in a luminaire, it may be required that all the drivers in the luminaire or series of luminaires receive a configuration unique to their installation.
One way for end users or LED light fixture manufacturers to be able to configure operating parameters of LED drivers in a safe, quick, and easy way is to load configuration parameters into the non-volatile storage memory medium, such as flash memory, of an integrated circuit (IC) for a Near-field communication (NFC) tag in the LED driver while the LED driver itself is unpowered, through the use of a configuration device equipped with a Radio-frequency identification (RFID) transceiver IC and antenna.
However, non-volatile memory storage is not suitable for the continuous data transfer needed for continuous digital dimming interfaces. For example, if a digital dimming controller with an NFC transceiver IC and antenna were permanently mechanically connected to the NFC antenna on the LED driver, and sent dimming commands to the LED driver every 200 milliseconds, the non-volatile memory (e.g., EEPROM) in the IC (e.g., NT3H1101 offered by NXP Semiconductors) would reach its 500 k write endurance limit in 83 days of run time.
It is accordingly desired to provide a lighting device such as an LED driver with a wireless communication interface having adequate functionality to support or otherwise provide a continuous digital dimming interface to external dimming control devices.
It may also be desirable that a luminaire or series of luminaires be able to report data regarding its particular operation, such as input or output power.
It may further be desirable to provide a relatively low cost interface circuit with inherent protection against the potential misapplication of line voltages.